The vortex shedding phenomena takes place in a range of Reynolds numbers greater than 1,000 and less than 400,000, where the Reynolds number based on the width of the bluff body generating the vortices is a dimensionless flow characteristic number equal to the product of the fluid velocity and the width of the bluff body divided by the kinematic viscosity of the fluid. The existing vortex shedding flowmeters determine the fluid velocity from the vortex shedding frequency as the vortex shedding frequency is proportional to the fluid velocity. The second generation vortex shedding flowmeters can measure the mass flow rate of the fluid in addition to the fluid velocity, as the amplitude of the lift force created by the sinuating streamlines trailing the vortex generating bluff body and experienced by a vortex sensing planar member disposed downstream of the bluff body is proportional to the dynamic pressure of the fluid flow, that is equal to one half of the fluid density times the square of the fluid velocity. Since the vortex shedding phenomena take place in the range of Reynolds numbers greater than 500 and less than 400,000, a well designed vortex shedding flowmeter should measure flow velocities in a range wherein the ratio of the maximum measurable velocity to the minimum measurable velocity (the turn-down ratio of the flowmeter) should be at least a few hundred to one. In actuality, the best of the existing vortex shedding flowmeters available at the present time has a turn-down ratio no better than 20 to 1. The poor performance of the existing vortex shedding flowmeters is due to the inability to detect the vortex-generated signals selectively and reject the noise signals generated by the structural vibration of the pipe lines, as the vortex-generated signals at low fluid velocities are very weak and submerged under the level of the noise signals. In order to improve the performance of the vortex shedding flowmeters, the vortex sensor measuring the frequency of the vortex shedding and/or the amplitude of the alternating fluid dynamic force created by the vortex shedding must detect the vortex signals selectively and reject the noise signals.